SIGNAL  OFFICE,  WAR  DEPARTMKNT. 


SIGNAL  SERVICE  NOTES  NO.  XII. 


THE  SPECIAL 


CHARACTERISTICS  OF  TORNADOES, 


WITH  PRACTICAL  DIRECTIONS 'FOR  THE  PROTECTION 
OF  LIFE  AND  PROPERTY. 


I'REPAREJ)   I'NDEK  THE  DIRECTION  OF 
HRIG-.     ,fe     JRVT.     INIAJ.     G-KN'J^,     \V.     B 

CHIEF  SIGNAL  OFFICER  OF  THE  ARMY, 


JOHN  P.  FIN  LEY, 

SERGEANT,  SIGNAL  coRI'S,   r.  S.  ARMY. 


15 V  ACTHOKITY  OF  THE  SECRETARY  OF  WAR. 


WASHINGTON   CITY  : 

SIGNAL  OFFICE. 

1884. 


SIGNAL  OFFICE,  WAR  DEPARTMENT. 


SIGNAL  SERVICE  NOTES  NO.  XII. 


THE  SPECIAL 


CHARACTERISTICS  OF  TORIADOES, 


WITH  PRACTICAL  DIRECTIONS  FOR  THE  PROTECTION 
OF  LIFE  AND  PROPERTY. 


I'RKI'AKKl)   I'NDKK  THK   Dl RUCTION  OK 

'Vr.    MA,T.    CS-KIT'I-,    "\V.    B. 

C'HIHF  SKiXAL  OFFICER  OF  THE  ARMY, 


BY 


JOHN  P.  FINLEY, 

SERGEANT,  SIGNAL  CORPS,   U.  S.  ARMY, 


BY 


WASHINGTON  CITY  : 
SIGNAL  OFFICE. 

1884. 


CONTENTS. 


I.— TERMS. 
II. — TORNADOES. 

III.— CONDITIONS  OF  FORMATION. 
IV. — PREMONITORY  SIGNS. 

V. — CHARACTER  OF  TORNADO  CLOUD  AND  MOTIONS. 
VI. — ELECTRICITY  AND  ITS  RELATIONS. 
VII. — PROTECTION  OF  LIFE. 
VIII. — PROTECTION  OF  PROPERTY. 
IX. — WHERE  TO  BUILD. 

X. — HOW  TO  BUILD  AND  USE  A  "  DUG-OUT"  A-ND  CELLAR  CAVES. 

XL — PROTECTION   IN   EMERGENCIES. 

XII PROTECTION  IN  TOWNS  AND  CITIES. 

XIII. — STATE  WEATHER  SERVICES. 

XIV. — .OBSERVATION  AND  RECORD  OF  TORNADOES. 


286148 


THE  SPECIAL  CHARACTERISTICS  OF  TORNADOES. 


The  present  pamphlet  considers  the  practical  bearing  of  some  of  the  results  of 
the  study  of  tornadoes,  and  will  answer  questions  as  to  the  object  of  this  systematic 
labor  under  government  authority  and  the  possibility  of  deriving  any  benefit  from 
the  knowledge  obtained  by  scientists. 

I. — TERMS. 

In  the  United  States,  the  terms  cyclone,  tornado,  and  hurricane,  are  frequently 
interchanged  in  ordinary  conversation  and,  in  the  minds  of  nine-tenths  of  the  peo- 
ple, these  terms  mean  one  and  the  same  thing.  This  is  not  altogether  surprising, 
considering  the  want  of  systematic  instruction  in  accurate  meteorological  knowledge, 
and  the  general  disposition  of  intelligent  minds  to  speculate  about  the  weather. 
Hut,  in  fact,  the  tornado  of  the  United  States  is  a  well-defined  species  of  storm,  dif- 
fering in  many  points  from  hurricanes,  cyclones,  and  thunder-storms,  and  it  is  the 
only  one  that  will  now  be  considered. 

II. TORNADOES. 

Omitting  consideration  of  the  tornadoes,  so  called  by  Portuguese  and  Spanish 
navigators  on  the  African  coast,  and  confining  our  attention  to  the  United  States,  it 
is  believed  that  these  storms  are  possessed  of  the  following  prominent  character- 
istics: The  general  direction  of  movement  of  the  tornado  is  invariably  from  a  point 
in  the  southwest  quadrant  to  a  point  in  the  northeast  quadrant.  The  tornado  cloud 
assumes  the  form  of  a  funnel,  the  small  end  drawing  near  to,  or  resting  upon,  the 
earth.  This  cloud  and  the  air  beneath  it  revolve  about  a  central  vertical  axis,  with 
inconceivable  rapidity,  and  always  in  a  direction  contrary  to  the  movement  of  the 
hands  of  a  watch.  The  destructive  violence  of  the  storm  is  sometimes  confined  to 
a  path  a  few  yards  in  width,  as  when  the  small  or  tail  end  just  touches  the  earth; 
while,  on  the  other  hand,  as  the  body  of  the  cloud  lowers,  more  of  it  rests  upon  the 
earth,  the  violence  increases,  and  the  path  widens  to  the  extreme  limit  of  eighty 
rods.  The  tornado,  with  hardly  an  exception,  occurs  in  the  afternoon,  just  after  the 
hottest  part  of  the  day.  The  hour  of  greatest  frequency  is  between  3  and  4  p.  m. 
Tornadoes  very  rarely,  if  ever,  begin  after  6  p.  m.  A  tornado  commencing  about 
5  p.  m.  may  continue  its  characteristic  violence  until  nearly  8  p.  m.,  which  means, 
only,  that  the  tornado  cloud  may  be  travelling  after  6  p.  m.,  or  after  7  p.  m.,  but  it 
does  not  develop,  that  is,  make  its  appearance,  for  the  first  time  after  those  hours. 
Outside  of  the  area  of  destruction,  at  times  even  along  the  immediate  edge,  the 
smallest  objects  often  remain  undisturbed,  although,  at  a  few  yards  distant,-  the 
largest  and  strongest  buildings  are  crushed  to  pieces.  At  any  point  along  the 
storm's  path,  where  there  is  opportunity  afforded  the  tornado  cloud  to  display  its 
power,  the  disposition  of  the  debris  presents  unmistakable  signs  of  an  action  of  the 
wind,  such  as  might  be  called  a  rotation,  from  the  right  through  the  front  to  the  left 
around  the  centre.  The  destructive  power  of  the  wind  increases  steadily  from  the 
circumference  of  the  storm  to  its  centre. 

Observations  with  a  single  isolated  barometer  will  not  indicate  the  approach  of  a 
tornado,  however  near  the  position  of  the  instrument  to  the  path  of  the  storm,  but 


r> 


TORNADO    CHARACTERISTICS. 


such  observations  arc  <>t  vnlir:  when,  a  number  are  displayed  upon  the  daily  weather 
map.  The  tomado  season  is  embraced  between  the  ist  of  April  and  the  ist  of  Sep- 
tember. The  months  of  greatest  frequency  are  June  and  July.  There  are,  however, 
instances  in  a  long  series  of  years  where  tornadoes  have  been  reported  in  every 
month  of  the  year.  Taking  the  w^hole  United  States  together,  it  is  found  that  the 
region  of  greatest  average  frequency  per  year,  per  square  mile,  embraces  the  follow- 
ing states  :  Georgia,  Illinois,  Indiana,  Iowa,  Kansas,  Missouri,  Ohio.  The  actual 
figures  are  about  as  given  in  the  following  table  : 

Relative  frequency  of  tornadoes.  1874  to  1880,  tnclu.<n-<  . 


State.                                                                       .r  = 

If 

6  8 

Connecticut  

o  5 

c  g 

Illinois 

Iowa 

c    c 

8  i 

Massachusetts                

0.8 

Minnesota  

...  .            8.4 

4  7 

Missouri            .    . 

6.5 

Nebraska  

7.6 

New  Hampshire 

79 

o  8 

New  York 

4  7 

North  Carolina  

5.1 

Ohio 

4  o 

Pennsylvania  . 

...              4  6 

3.4 

Tennessee  . 

....           4.6 

I.O 

Vermont              .  .    . 

...                                          5    T, 

All  of  New  England  ... 

6.8 

1-5 


•3- 

6. 

3- 

3- 

6.9 

1.4 

0.9 

1.6 

2.6 

i.i 

5-0 

i.S 

0.4 

0.6 

2.5 

1.8 

2.6 


1.9 

0.2 

1.4 

2.1 


0.30 

0.20 
0.40 
0.62 

i-l3 
0.88 
0.58 
0.85 
0.34 

1. 12 

0.29 
0.31 
0.23 

0.77 
0.24 
o.44 
o.75 
0-53 
0.35 
o.b4 
0.46 
o.47 
0.41 

0.20 

0.26 

0.31 


It  is  not  within  the  province  of  this  memoir  to  discuss  at  length  the  points  of  dif- 
ference or  harmony,  or  enter  into  an  intricate  analysis  of  meteorological  phenomena 
and  the  multiform  operations  of  atmospheric  changes  attending  the  origin,  develop- 
ment, and  complete  formation,  of  tornadoes.  On  the  contrary,  it  is  desired  to  pre- 
sent a  minute  consideration  of  the  peculiarities  of  tornadoes,  with  a  view  to  placing 
at  the  disposal  of  the  people  most  interested  the  facts  and  practical  results  of  past 
and  present  investigations  of  this  terrible,  yet  most  interesting,  class  of  storms. 

III.  —  CONDITIONS    OF    FORMATION. 


These  may  be  divided  into  classes  as  follows  : 

First:  those  within  the  reach  of,  and  which  may  be  known  or  investigated  by,  an 
isolated  observer.  To  the  single  observer,  located  at  his  farm,  workshop,  or  store, 
there  are  important  atmospheric  conditions  which  he  may  carefully  watch  and  study 
with  profit,  viz.  :  the  gradual  setting  in  and  prolonged  movement  of  the  air  from  the 
north  and  south  points  ;  the  gradual,  but  continued,/^//  of  the  thermometer  during 
the  prevalence  of  the  former  currents,  and  a  rise  during  the  predominence  of  the 
latter. 


TORNADO    CHARACTERISTICS.  7 

If  the  northerly  currents  are  the  prevailing  air  movements  at  the  place  of  obser- 
vation, the  atmospheric  disturbance  is  forming  southward,  but,  if  the  prevailing  air 
currents  are  from  the  south,  then  to  the  northward  of  the  observer. 

Carefully  study  cloud  development,  color  as  well  as  form  ;  also,  manner  and 
direction  of  approach.  Clouds  render  visible  the  air  currents,  and  are  full  of  meaning. 

A  study  of  the  currents  of  the  atmosphere  would  be  impossible  without  their 
existence,  and  that,  too,  in  a  variety  of  forms.  Dispense  with  cloud  formation,  and 
the  face  of  the  sky  would  become  blank,  and  severe  storms  no  longer  visible. 

Wind  direction,  temperature,  and  clouds,  are  proper  subjects  of  observation  and  in- 
vestigation by  the  isolated  observer.  The  barometer  is  of  less  importance  in  this  line 
of  inquiry,  unless  the  barometric  observations  can  be  promptly  compared  with  those 
taken  at  other  points  near  by  and  at  the  same  moment  of  time.  The  tornado  itself 
is  an  extremely  local  affair,  and  the  accompanying  barometer  changes  do  not  affect 
a  large  extent  of  country.  Probably  if  a  barometer  were  placed  in  the  immediate 
track  of  the  tornado  cloud,  it  would  not,  with  any  certainty,  indicate  the  presence  of 
the  storm  until  the  crashing  winds  had  fallen  upon  the  instrument. 

Second:  conditions  that  can  only  be  witnessed  and  analyzed  by  the  intelligent  eye 
of  the  student  of  the  Weather  Map. 

From  this  panoramic  view  of  the  situation  a.  vast  extent  of  country  can  be  most 
carefully  watched  from  hour  to  hour,  for  days,  weeks,  or  months.  Atmospheric  con- 
ditions on  opposite  sides  of  the  probable  course  of  the  storm  can  be  watched  from 
their  inception,  and,  in  any  new  relations,  easily  detected  and  analyzed.  From  a 
study  of  the  Weather  Map,  it  has  been  found  that  the  formation  of  what  is  termed 
a  barometric  trough  or  elongated  area  of  low  pressure  (where  the  barometer  stands 
below  the  normal  for  that  region  and  for  the  hour  of  observation)  precedes  the 
occurrence  of  tornadoes  in  the  lower  Mississippi  valley,  or  adjoining  states  to  the 
south  and  east.  This  low  pressure  area  assumes  the  form  of  an  ellipse,  and  gen- 
erally extends  from  southwest  to  northwest  between  northern  Texas  and  the  upper 
lake  region.  Such  a  depression  may  lie  between  the  central  Mississippi  valley  and 
the  lower  lake  region,  trending  northward  just  south  of  Michigan  and  over  the  Ohio 
valley.  The  longer  axis  of  either  of  these  depressions  is  easily  estimated,  while 
the  shorter  axis  may  be  stated  as  generally  varying  from  three  to  five  hundred  miles. 
To  the  north  of  the  longer  axis,  even  for  a  distance  of  several  hundred  miles,  the 
winds  are  found  to  proceed  from  any  or  all  points  between  northeast  and  northwest 
with  comparatively  low  temperatures,  accompanied  sometimes  by  a  cold  rain  or  even 
snow.  South  of  the  longer  axis,  and  generally  to  a  greater  distance,  the  winds  come 
from  any  or  all  points  between  southeast  and  southwest,  accompanied  by  compara- 
tively high  temperature,  high  humidty,  and  often  dashes  of  quite  heavy  rain. 

As  these  conditions  continue  to  prevail,  the  map  shows  an  increasing  contrast  of 
temperature  on  the  north  and  south  sides  of  the  longer  axis,  and  as  this  contrast  of 
temperature  gradient  increases,  the  formation  of  clouds  commences  in  earnest. 

An  isolated  observer  in  the  warm  south  wind  on  the  south  side  of  the  longer  axis 
of  course  can  know  nothing  of  the  existence  of  this  cold,  dry  air  to  the  north  of  him, 
but  he  sees  huge  masses  of  clouds  of  dark  and  portentous  appearance  bank  up  in  the 
northwest  and  southwest  with  amazing  rapidity,  and  soon  the  scene  becomes  one  of 
awful  grandeur. 

The  upper  currents  of  air  are  thus  indicated  by  the  cloud  formations.  The  con- 
densation of  vapor  increases  rapidly,  and  huge  volumes  of  air  rush  upward.  The 
outward  indication  of  the  formation  of  a  tornado  i£>  first  shown  in  the  whirling,  dash- 
ing clouds  over  the  broken  surface  of  the  heavy  bank  of  condensed  vapor  forming 
the  background  ;  a  scene  not  easily  depicted  or  realized  by  one  who  has  not  witnessed 
it,  but  never  to  be  effaced  from  the  memory  of  the  actual  observer.  The  next  stage 
in  the  further  development  of  this  atmospheric  disturbance  is  the  gradual  descent  of 


8  TORNADO    CHARACTERISTICS. 

the  funnel-shaped  cloud.      The   tornado  is   now  before-   us,  not   fully  developed,  but 
soon  to  acquire  that  condition. 

IV. PREMONITORY     SIGNS. 

On  the  day  of  the  storm,  and  for  several  hours  previous  to  the  appearance  of  the 
tornado  cloud,  what  indications  of  its  probable  formation  and  approach  are  within 
the  comprehension  of  an  ordinary  observer  and  can  readily  be  detected  by  him  ?  A 
sultry,  oppressive  condition  of  the  atmosphere,  described  by  various  observers 
as  follows  :  "  I  really  experienced  a  sickly  sensation  under  the  influence  of  the  sun's 
rays."  "I  was  compelled  to  stop  work  on  account  of  the  peculiar  exhaustion  expe- 
rienced from  physical  exertion."  "  It  seemed  as  if  the  lightest  garments  that  I  could 
put  on  were  a  burden  to  me."  "  There  was  not  a  breath  of  air  stirring."  "The  air> 
at  times,  came  in  puffs,  as  from  a  heated  furnace."  "  I  felt  a  want  of  breath,  the  a  in- 
frequently appearing  too  rarified  to  breathe  freely."  "  I  was  startled  at  the  sudden 
and  continued  rise  in  the  thermometer,  especially  at  this  season  of  the  year."  "  It 
was  terribly  oppressive  ;  it  seemed  as  if  the  atmosphere  was  unusually  heavy  and 
pressing  down  on  me  with  a  great  weight." 

Enough  examples  have  now  been  cited  to  indicate  the  effects  and  signs  of  this 
oppressive  sultriness.  Other  signs  may  be  found  in  the  development  and  peculiar 
formation  of  the  clouds  in  the  western  horizon.  Sometimes  these  peculiar  clouds 
extend  from  the  southwest  through  the  west  by  the  north  to  the  northeast.  More 
frequently,  however;  they  form  in  the  northwest  and  southwest,  sometimes  com- 
mencing, first  in  the  former  quarter  and  then  again  in  the  latter,  but  in  either  case 
they  are  equally  significant.  The  marked  peculiarity  of  the  clouds  is  found  to  oc- 
cur not  only  in  the  form  but  in  the  color  and  character  of  development. 

The  sudden  appearance  of  ominous  clouds,  first  in  the  southwest  and  then  almost 
immediately  in  the  northwest  or  northeast  (or  perhaps  reversed  in  the  order  of 
their  appearance),  generally  attracts  the  attention  of  the  most  casual  observer.  In 
almost  all  cases  these  premonitory  clouds  are  unlike  any  ordinary  formation.  If 
they  are  light  their  appearance  resembles  smoke  issuing  from  a  burning  building  or 
straw  stack,  rolling  upward  in  fantastic  shapes  to  great  heights  ;  sometimes  they 
are  like  a  fine  mist,  or  quite  white  like  fog  or  s^eam.  Some  persons  describe  these 
light  clouds  as  at  times  apparently  iridescent  or  glowing,  as  if  a  pale  whitish  light 
issued  from  their  irregular  surfaces.  If  the  premonitory  clouds  are  dark  and  pre- 
sent a  deep  greenish  hue,  this  fairly  forbodes  very  great  evil.  So,  also,  if  they 
appear  jet  black  from  the  centre  to  circumference,  or  if  this  deep  set  color  appears 
only  at  the  centre,  gradually  diminishing  in  intensity  as  the  outer  edges  of  the 
cloud  or  bank  of  clouds  are  approached.  Sometimes  these  dark  clouds,  instead  of 
appearing  in  solid  and  heavy  masses,  roll  up  lightly  but  still  intensely  black,  like 
the  smoke  from  an  engine  or  locomotive  burning  soft  coal.  They  have  been  de- 
scribed as  of  a  purple  or  bluish  tinge,  or  at  times  possessed  of  a  strange  lividness, 
or  frequently  dark  green,  and  again  of  an  inky  blackness  that  fairly  startles  you 
with  its  intensity*. 

The  following  are  extracts  from  reports  of  observers  :  "They  were  the  worst 
looking  clouds  I  ever  saw;  perfectly  awful."  "The  clouds  seemed  to  be  boiling 
up  like  muddy  water,  the  upper  surface  of  the  cloud  reminding  me  of  the  incessant 
eddies  or  whirls  seen  in  the  muddiest  portions  of  the  Missouri  river."  "  I  saw  two 
whirling  circles  of  lightish  gray  clouds  in  the  west  ;  they  were  acting  independent 
of  each  other,  and  moved  slowly  inward  toward  each  other  from  opposite  directions. 
The  clouds  were  very  low  ;  seemed  to  be  on  the  earth,  the  wind  in  contrary  direc- 
tions across  the  face  of  the  western  sky,  and  surrounding  clouds  in  great  confusion." 
"  Observed  clouds  moving  in  all  directions  ;  some  of  a  dark  green  color,  others 
white  as  steam."  "  The  lower  end  of  the  cloud  was  \ery  while,  like  fog."  "  I  saw 


TORNADO    CHARACTERISTICS.  11 

a  great  smoke,  and  supposed,  at  first,  it  was  a  fire."  "  I  saw  a  terrible  cloud,  of  a 
dark  purplish  color."  "  There  was  a  peculiar  and  terrifying  look  to  the  clouds."  "  1 
saw  a  green  cloud  in  the  northwest,  surrounded  by  others  not  so  deep  set  in  color. 
Under  the  cloud  from  the  southwest,  there  came  a  large  number  of  little  thunder- 
heads,  some  very  dark,  but  others  as  white  as  steam.  They  seemed  to  be  separated 
and  running  very  low.  I  never  saw  clouds  so  low  before.  Pretty  soon  they  began 
to  go  in  all  directions,  some  up,  some  down,  right  and  left,  backwards  and  forwards. 
I  next  saw  a  cloud  that  looked  even  all  over  in  color  and  very  white,  the  edges  being 
pretty  regular.  It  moved  remarkably  steady,  and  seemed  to  be  right  under  the  edge 
of  the  cloud  from  the  southwest."  "  I  noticed  a  strange  action  in  the  clouds,  and 
saw  a  cloud  rolling  on  the  ground  coming  from  the  southwest."  "  The  ground  was 
covered  with  white,  steamv  looking  clouds,  that  prevented  one  from  seeing  any  dis- 
tance." "  Two  clouds,  one  from  the  northwest,  and  the  other  from  the  southwest, 
seemed  to  meet,  and,  after  meeting,  passed  still  lower.  Above  their  place  of  meet- 
ing, black  smoke  appeared  in  very  peculiar  shape.''  "  The  air  presented  a  very  pe- 
culiar appearance;  it  seemed  to  be  in  different  shaded  strata  and  quite  marked."  "  At 
the  bottom  of  the  cloud  a  hazy  appearance  rose  up,  obstructing  the  view,"  "  Two 
clouds  came  together  ;  one  from  the  southwest  and  the  other  from  the  northwest ; 
the  latter  was  the  higher,  and  the  former  the  heavier  and  looked  the  worse."  "  A 
heavy  cloud  spread  out  before  us  to  a  width  of  about  six  hundred  feet,  and  as  black 
as  night." 

The  peculiarities  of  the  clouds  while  they  are  forming  is  another  interesting  and 
significant  feature  which  should  be  carefully  watched.  Under  ordinary  circum- 
stances, clouds  form,  move,  arid  disappear,  without  exciting  special  remark  or,  per- 
haps, thought,  from  the  casual  or  even  the  interested  observer.  In  the  event  of  a 
Ihunder-storm  or  hail-storm,  the  movement  and  disposition  of  the  clouds  are  not 
looked  upon  with  fear  or  as  possibly  possessed  of  a  power  to  create  great  havoc,  but 
on  the  occasion  of  a  tornado  the  formation  and  movement  of  the  clouds  strike  most 
persons  dumb  with  fear.  There  seems  to  be  some  strange  connection  between  the 
almost  simultaneous  appearance  of  clouds  in  the  southwest  and  northwest,  possess- 
ing, as  they  do,  such  unusually  threatening  forms.  As  they  approach  from  oppo- 
site directions,  they  are  suddenly  thrown  into  the  greatest  confusion,  breaking  up,  as 
it  were,  into  small  portions,  which  clash  pell-mell  over  each  other  and  in  every  di- 
rection, now  darting  toward  the  earth,  now  rushing  upward  to  considerable  heights 
or  at  moderate  elevations,  rolling  over  each  other  in  a  well  developed  whirl.  An 
observer,  in  describing  the  approach  of  the  clouds  from  the  southwest  and  north- 
west, stated  that  they  "came  together  with  a  terrific  crash,  as  if  thrown  from  the 
mouths  of  cannons."  Generally,  following  closely  upon  the  existence  of  this  con- 
dition, the  funnel-shaped  tornado  cloud  appears  against  the  western  sky,  moving 
boldly  to  the  front  from  without  this  confused  mass  of  flying  clouds.  As  the  tornado 
cloud  advances,  these  clouds  continue  to  play  about  its  top  and  sides,  constituting  a 
characteristic  feature  of  the  scene. 

Another  and  invariable  sign  of  the  tornado's  approach  is  a  heavy  roaring,  which 
augments  in  intensity  as  the  tornado  cloud  advances.  This  roaring  is  compared  to 
the  passage  of  a  heavily  loaded  freight  train  moving  over  a  bridge  or  through  a 
deep  pass  or  tunnel,  or  as  heard  on  damp  mornings  when  the  sound  is  very  clear 
and  loud.  At  times  the  roaring  has  been  so  violent  that  persons  have  compared  it 
to  the  simultaneous  "rush  of  10,000  trains  of  oars."  Again,  the  roaring  is  likened 
to  the  low  rumbling  of  distant  thunder.  The  varying  intensity  of  the  roar,  as  here' 
represented,  is  apparently  due  to  the  lack  of  uniformity  in  the  positions  of  the  various 
observers  with  respect  to  the  advancing  tornado  cloud.  Those  situated  nearest  the 
cloud,  other  things  being  equal,  experience  the  loudest  roar,  while  to  those  at 
greater  distances  the  noise  is  proportionally  weaker.  In  any  event,  however,  the 


10  TORNADO    CHARACTER  ISTICS. 

noise  is  sufficiently  peculiar  and   distinct  to   create   alarm,  and  as  a  means  of  -Burn- 
ing should  not  be  overlooked  under  any  pretext. 

V. CHAKACTKK  ()F   TORNADO  CLOUD  AND  ATTENDING   MOTIONS. 

The  tornado  cloud  is,  generally  speaking,  at  its  first  formation,  funnel-shaped, 
that  is  to  say,  it  tapers  from  the  top  downward,  not  always  in  the  same  degree  with 
every  appearance  of  the  cloud,  but  the  lower  end  of  it  (the  part  nearest  the  earth) 
is  invariably  the  smallest,  and  this,  too,  whatever  may  be  the  inclination  of  the  cen- 
tral axis  of  the  cloud  to  the  vertical  or  plumb  line.  As  seen  in  different  positions 
and  stages  of  development  by  various  observers,  located  differently,  the  tornado 
cloud  has  been  called  "balloon-shaped;"  "basket-shaped;"  "egg-shaped;"  trailing 
on  the  ground  like  the  tail  of  an  enormous  kite;"  "of  bulbous  form;"  "like  an  ele- 
phant's trunk;"  &c.,  &c.  In  the  majority  of  instances,  however,  observers  describe 
the  cloud  as  appearing  like  an  upright  funnel.  When  the  small  end  of  the  cloud 
just  reaches  to  the  earth,  the  violence  of  its  whirl  causes  a  peculiarly  formed  cloud 
of  dust,  and  finely  divided  debris,  around  which  play  small  gatherings  of  con- 
densed vapor.  To  all  appearances  now,  the  tornado  cloud  has  two  heads,  one  on 
the  surface  of  the  earth  and  the  other  in  the  sky,  the  bodies  of  each  joining  in  mid- 
air and  tapering  both  ways  with  the  smallest  diameter  at  their  junction.  In  other 
words,  the  cloud  now  assumes  the  shape  of  an  hour-glass,  and  the  lower  portion  dis- 
plays extraordinary  destructive  violence.  This  last  and  most  fatal  form  of  the 
tornado  cloud  is  fortunately  not  a  constant  feature  of  the  storm.  The  tornado  cloud 
is  constantly  changing  from  the  hour-glass  form  to  that  of  the  upright  funnel,  or 
some  other  intermediate  shape  previously  referred  to. 

The  various  gradations  of  form,  not  any  of  which,  however,  affect  the  stereotyped 
relation  between  the  size  of  top  and  bottom,  number  some  twenty-five  or  thirty,  so 
far  as  reliable  information  has  been  secured  upon  this  point.  These  variations  of 
form  depend  upon  the  peculiar  movements  of  the  whirling  currents  of  air  within 
and  about  the  tornado  cloud,  the  direction  of  the  currents  being  outlined  to  the  eye 
by  the  singular  disposition  of  the  rapidly  condensing  masses  of  vapor.  The 
characteristic  motions  of  the  tornado  cloud  number  four,  and  are  described  as 
follows  : 

No.  I.  is  called  the  whirling  or  gyratorv  motion  of  the  tornado,  which  is  invaria- 
bly from  the  right  by  the  front  around  to  the  left.  This  whirling  motion,  in  all  prob- 
ability, exists  in  the  air  preceding  the  formation  of  the  tornado  cloud,  and  should, 
therefore,  be  placed  first  in  order  of  consideration.  Its  velocity  is  far  in  excess  of 
any  of  the  others.  Many  efforts  have  been  made,  but  most  of  them  altogether 
fruitless,  to  estimate  this  velocity,  and  results,  ranging  from  100  to  800  and  even 
1,000  miles  per  hour,  have  been  deduced,  but  no  great  precision  can  be  assigned  to 
such  figures.  In  the  majority  of  instances  the  determinations  have  ranged  between 
100  and  500  miles  per  hour.  Theoretical  velocities  of  over  2,000  miles  per  hour, 
based  upon  certain  assumed  atmospheric  conditions,  have  been  deduced.  Such 
velocities  are  mathematically  possible  but  not  meteorologically  probable. 

The  uncertainty  of  the  computed  velocities  results  largely  from  the  difficulty 
attending  the  acquirement  of  absolutely  reliable  data.  In  all  carefully  conducted 
investigations  heretofore  made,  such  a  long  time  has  intervened  between  the  occur- 
rence of  the  storm  and  the  arrival  of  the  person  authorized  to  commence  the  work, 
that  valuable  and  satisfactory  results  in  this  direction  are  precluded.  It  is  always 
of  prime  importance  to  ascertain  definitely  what  portion  of  a  building  or  other 
object  was  first  struck  by  the  wind  and  what  the  configuration  and  inclination  of 
the  exposed  surface.  As  a  rule  such  determination  has  been  rendered  next  to  im- 
possible by  the  rapidity  with  which  devasted  districts  recover  from  the  violence  of 
the  storm.  This  statement  is  a  most  praiseworthy  and  well  deserved  commentary 


TORNADO    CHARACTERISTICS.  11 

on  the  exemplary  industry  and  determined  spirit  of  the  people,  especially  of  the 
lower  Missouri  valley. 

With  the  gyratory  motion  of  the  tornado  cloud  objects  are  drawn  inward  to  the 
centre  of  the  storm,  and  then  carried  violently  upward  by  a  spirally  inward  and  up- 
ward motion  which  fairly  crushes  and  grinds  into  pieces  buildings,  trees,  and  what- 
ever else  stands  in  the  line  of  the  advancing  cloud.  The  spirally  upward  motion 
throws  the  ascending  debris  in  a  circular  manner  outward  at  the  top  of  the  tor- 
nado cloud.  This  debris,  when  beyond  the  central  whirl  of  the  cloud,  falls  to  the 
earth,  but  in  such  a  manner  and  so  disposed  as  to  indicate  the  character  of  the  force 
which  acted  upon  it. 

No.  II.  is  called  the  progressive,  motion  of  the  tornado  cloud  taken  as  a  whole,  or 
the  motion  which  determines  the  cloud's  progress  from  one  point  to  another.  The 
rate  of  progressive  velocity  ranks  next  in  order  to  the  velocity  of  motion  No.  I., 
although  it  is  certainly  at  all  times  far  below  the  high  degree  of  the  latter. 

The  rate  of  progress  of  the  tornado  cloud  is  subject  to  great  variability  through- 
out the  duration  of  any  one  storm.  Some  observers  have  indicated  the  movement 
by  the  following,  expressions  :  "  All  in  an  instant."  "  Gone  in  a  moment."  "Quicker 
than  thought."  "  Without  a  moment's  warning."  "  It  moved  no  faster  than  a  horse 
gently  galloping."  "  I  just  saw  what  it  was,  and  then  it  was  all  over."  "  Before  I 
had  time  to  turn  about  in  my  tracks  it  flashed  by  me."  "  It  seemed  to  remain  almost 
motionless,  as  if  held  to  the  ground  by  some  mysterious  force."  "  I  shuddered, 
held  my  breath,  and  the  monster  had  vanished."  "It  seemed  to  move  no  faster 
than  I  could  run." 

These  estimations  of  velocity  are  not  to  be  taken  literally.  The  circumstances 
under  which  the  impressions  were  received  must  be  considered,  viz.:  undue  excite- 
ment, or  abject  terror.  However,  the  comparative  results  are  important,  and,  to  a 
certain  extent,  reliable.  In  view  of  them,  people  will  at  least  not  underestimate  the 
awful  grandeur  of  the  panorama,  or  fall  into  the  fatal  mistake  of  encouraging  a  belief 
that  the  tornado  is  not  what  the  united  experience  of  all  observers  has  portrayed  it. 

Such  data  will  not  answer,  however,  to  figure  on  very  closely,  but  the  items,  aver- 
age diameter  of  cloud,  actual  time  (local  or  standard),  and  measured  distances,  are 
greatly  desired  as  a  basis  for  accurate  study.  Reliable  data  are  very  difficult  to 
obtain,  especially  of  time.  This  fact  should  be  thoroughly  appreciated  by  observers, 
and  every  reasonable  effort  made  by  them  to  examine  their  clocks  or  watches  upon 
the  approach  and  passage  of  a  tornado  cloud.  Generally  speaking,  it  is  a  good  habit 
to  form,  of  jotting  down,  in  some  place  of  ready  reference,  the  hour,  day,  month,  and 
year,  of  notable  events. 

In  regard  to  this  matter  of  time,  so  far  as  past  determinations  can  be  valued,  the 
progressive  velocity  of  the  tornado  cloud,  taken  as  a  whole,  is  variously  estimated 
at  from  twenty-five  to  seventy-five  miles  per  hour.  The  former  is  perhaps  too  low 
and  the  latter  quite  likely  too  high,  and,  although  in  both  instances  they  represent 
the  extremes,  yet  either  of  the  above  velocities  may  have  existed  for  short  intervals. 
The  general  average  is  probably  about  forty  miles  per  hour. 

No.  III.  is  termed  the  rising  •&&.&  falling  motion  of  the  tornado  cloud,  the  character 
of  which  finds  definition  in  the  following  expressio  \s  from  various  witnesses:  "  The 
top  of  the  cloud  seemed  to  pop  up  and  down,  and  then  to  rush  forward."  "  It 
bounded  over  the  ground  like  a  ball."  "  It  was  the  strangest  jumping  and  flopping 
object  I  ever  saw."  "At  times  it  seemed  to  lash  the  earth  in  terrific  fury  with 
its  huge  tail."  "It  came  along,  popping  up  and  down  in  a  most  fantastic  way." 
"Rising  up  like  the  uncoiling  of  a  huge  rope,  it  cut  loose  from  the  earth  and  passed 
over  us  with  a  horrible  \vhizzing  sound."  "  Ever  and  anon  it  would  shoot  directly 
upward  from  the  earth,  sometimes  with  great  rapidity,  and  then  again  quite  slowly, 
each  time  dashing  to  the  surface  with  renewed  vigor." 


1:2  TOKXA1X) 

It  is,  perhaps,  clearly  seen  that  this  is  a  distinct  motion,  with  striking  peculiarities 
which  define  its  character.  Sometimes,  upon  the  lifting  of  the  tornado  cloud  from 
the  earth,  it  does  not  again  descend  for  a  distanceV>f  several  miles,  at  times  making 
the  return  movement  or  descension  twenty  or  thirty  miles  distant,  the  intervening 
space  proving  a  complete  blank  in  its  track.  More  frequently,  however,  these  gaps 
are  from  one  to  live  miles  in  length. 

While  the  tornado  cloud  is  traversing  the  atmosphere  at  some  considerable  dis- 
tance from  the  earth,  it  may  reach  down  so  low  as  to  just  skim  over  the  tops  of  the 
highest  trees;  descend  to  a  level  with  the  roofs  of  buildings,  simply  scaling  off  the 
shingles  in  spots  or  entirely  on  one  side,  leaving  the  roof-boards  and  rafters  un- 
moved ;  removing  the  tops  of  chimneys  ;  taking  out  all  the  fans  in  the  wheels  of  a 
windmill  and  leaving  every  portion  (even  the  tail)  of  the  remainder  of  the  mill 
unharmed  ;  taking  off  the  cornice  without  disturbing  the  remainder  of  the  roof  ; 
removing  simply  the  top  boards,  or  one  or  two  of  the  top  rails,  of  a  fence. 

The  tornado  cloud  may,  however,  remain  at  a  perfectly  safe  distance  throughout 
its  aerial  course  and  where  it  may  be  seen  at  a  great  height,  moving  solitary  and 
alone,  like  a  huge  balloon.  While  in  this  condition  it  has,  not  a  few  times,  been  un- 
wittingly taken  for  the  latter  object,  but  the  mystery  and  sensation  were  entirely  dis- 
pelled when  the  news  came  in  from  the  surrounding  country  of  the  frightful  power 
of  this  now  silent  monster. 

There  is  still  another  feature  of  motion  No.  III.:  upon  rising  from  the  earth  and 
passing  through  a  few  uncertain  struggles,  apparently  to  decide  upon  the  final  direc- 
tion of  movement,  the  tornado  cloud  is  ultimately  lost  sight  of  in  tht  surrounding 
clouds,  but  reappears  suddenly  at  some  point,  either  to  descend  or  to  remain  above 
at  a  safe  distance. 

.No  IV.  is  called  the  zigzag  motion,  or  swaying  of  the  tornado  cloud  from  side  to 
side  of  a  general  line  of  progress.  This  motion  is  sometimes  quite  suddenly  per- 
formed, but  generally  it  is  a  moderately  slow  movement,  and  one  that  can  be  watched 
and  easily  identified.  It  seems  to  occur  most  frequently  just  as  the  tornado  cloud 
touches  the  earth,  as  described  in  the  preceding  motion  No.  III.,  when  the  cloud  will 
often  diverge  about  an  equal  distance  on  either  side  of  the  central  line  of  movement. 

At  the  commencement  of  this  motion,  the  tornado  cloud  always  moves  first  to  the 
left  (N.  N.  \V.)  and  then  to  the  right  (E.  S.  E.).  On  the  return  movement,  the  cloud 
may  or  may  not  cross  the  major  axis  to  the  right  (E.  S.  E. ).  The  zigzag  movement 
from  one  side  to  the  other  of  the  central  line  of  progressive  action  may  continue 
for  several  miles,  or  it  may  be  cut  short  after  the  first  few  moves. 

The  regularity  of  this  peculiar  action  appears  to  be  in  connection  with  indraughts 
of  violent  currents  of  air  from  the  south  side  of  the  major  axis,  which  frequently 
advance  (only  from  the  left  side)  and  give  evidence  of  their  existence  by  swaths  or 
narrow  paths  of  destruction  (alternating  with  spaces  of  no  damage )  cut  inward  toward 
and  joining  with  the  central  line  or  track.  The  tornado  cloud  may,  upon  the  return 
movement,  whether  executed  upon  the  north  or  south  side  of  the  major  axis,  fail  to 
cross  it,  but  upon  reaching  it  continue  onward  in  the  central  line  of  movement  to 
the  northeast. 

The  distance  travelled  by  the  tornado  cloud  in  departing  from  the  major  axis, 
either  to  the  right  or  left,  is  subject  to  considerable  variability,  ranging  from  forty 
or  fifty  yards  to  nearly  as  many  rods.  While  executing  this  /ig/ag  motion  it  very 
frequently  happens  that  the  tornado  cloud  simply  skims  over  the  earth,  without 
manifesting  its  extreme  violence. 

V  I. KI.Ki'TRiriTY. 

The  rain  and  hail  which  sometimes  precede,  and  at  other  times  follow,  the  tor- 
nado cloud,  but  always  accompany  the  heavy  clouds  which  form  in  the  north  and 


TORXADO    CHARACTERISTICS.  13 

west,  is  generally,  but  not  always,  attended  by  lightning  ;  sometimes  by  most  violent 
manifestations  and  then  again  by  occasional  flashes.  The  most  terrific  displays  are 
reported  during  the  heavy  precipitation  which  often  occurs  ten  or  twenty  minutes 
after  the  tornado  cloud  has  passed.  Very  often  flashes  are  observed  in  the  dark 
clouds  which  begin  to  rise  above  the  western  horizon  an  hour  or  more  before  the 
storm. 

What  relation  has  electricity  to  the  formation  and  power  of  the  tornado  clouds  ? 
Most  persons  are  utterly  at  a  loss  to  account  for  the  prodigious  power  manifested  in 
the  destructive  effects  of  the  tornado.  If  they  make  the  least  attempt  to  philosophize 
upon  the  subject,  they  are  determined  to  assign  the  cause  to  some  mysterious  inter- 
ference of  electrical  force.  Whenever  a  piece  of  iron  is  bent,  broken,  twisted,  or 
carried  a  considerable  distance,  a  tree  torn  up  by  the  roots,  or  clothing  snatched 
from  the  body,  it  is  attributed  to  electricity.  The  fact  that  lightning  does  not  ap- 
pear in  the  tornado  cloud  itself  is  explained  away  by  supposing  some  incomprehen- 
sible modification  of  its  usual  character.  There  is  a  dogmatic  predisposition  to 
attribute  everything  unusual  to  this  one  member  of  the  category  of  physical  forces. 
Of  course  it  is  the  easiest  way  to  get  rid  of  a  difficult  problem. 

Even  if  electricity  is  present,  there  is  no  requirement  of  its  intervention  to  pro- 
duce the  force  required.  It  is  plainly  evident  that  the  movement  of  a  current  of  air 
at  the  rate  of  two  hundred  to  five  hundred  miles  per  hour  is  sufficiently  powerful  to 
demolish  the  strongest  buildings,  lift  a  piece  of  iron  or,  if  necessary,  distort  its 
shape. 

VII. PROTECTION    ol-     LIFK. 

How  can  people  save  their  lives  or  avoid  terrible  injuries  ?  In  regard  to  this,  much, 
if  not  everything,  depends  upon  the  manner  and  direction  a  person  moves,  together 
with  the  distance  of  the  tornado  cloud,  its  direction,  and  the  kind  of  motion  prevail- 
ing at  the  instant  one  determines  upon  changing  his  position. 

We  will  now  suppose  the  various  conditions,  and  proceed  to  point  out  the  neces- 
sary action  in  each  instance.  In  all  cases  it  is  granted,  for  the  sake  of  convenience 
in  illustration,  that  you  are  in  front,  or  situated  directly  in  the  line,  of  the  advancing 
tornado  cloud.  Under  these  circumstances,  if  progressive  motion  No.  II.  of  the 
cloud  is  prevailing  and  your  distance  from  it,  say,  eighty  rods  (one-fourth  mile)  or 
more,  moz'c  directly,  and  with  all  possible  dispatch,  to  the  north.  Whenever  this 
motion  is  prevailing,  ahuavs  run  to  the  north,  unless  in  so  doing  you  would  be  obliged 
to  cross  the  entire  path  of  the  storm.  A  sharp  glance  to  the  u'estward  will  tell  you 
whether  you  are  about  on  the  southern  edge  of  the  probable  path  of  the  tornado 
cloud,  or  more  to  the  north.  If  in  the  centre  or  half  way  between  the  centre  and  the 
southern  edge,  your  chances  are  best  in  a  direct  course  to  the  north.  If  further  to 
the  south,  move  directly  and  very  rapidly  to  the  south,  bearing  slightly  east.  In  no 
event  should  you  ever  run  directly  to  the  east  or  northeast.  Suppose  the  tornado 
cloud  to  be  distant  from  you  (W.  or  SW. )  eighty  rods  (one-fourth  mile)  and  its  pro- 
gressive velocity  sixty  miles  per  hour,  it  would  advance  one  mile  in  sixty  seconds, 
or  eighty  rods  in  fifteen  seconds.  Assuming  the  average  width  of  the  destructive 
path  of  the  tornado  cloud  to  be  forty  rods  and  your  position  at  the  centre  of  that 
path,  it  will  be  seen  that  you  have  fifteen  seconds  in  which  to  reach  the  outer  edge 
of  the  path  to  the  north  (a  distance  of  twenty  rods)  before  the  tornado  cloud  could 
arrive  at  your  location. 

An  extreme  case  has  been  assumed  in  every  particular.  Most  persons  first  see  the 
tornado  cloud  at  a  much  greater  distance,  from  one  to  three  miles,  sometimes  five  and 
even  ten  miles  on  the  prairies,  Of  course  at  the  unusual  distance  of  five  or  ten  miles 
you  could  not  determine  very  satisfactorily  its  probable  course,  especially  with  re- 
gard to  your  buildings  or  the  safety  of  your  own  location.  Watching  the  approach 


14  TORNADO    CHARACTERISTICS. 

of  the  tornado  cloud  closely  at  a  distance  of  ten  miles,  and  from  that  position  on 
and  on  in  its  eastward  course  until  it  came  within  a  mile  or  so  of  your  point  of  ob- 
servation, would  give  you  sufficient  opportunity  to  predict  its  probable  course  in 
regard  to  your  location.  When  that  matter  is  settled  satisfactorily  to  your  judg- 
ment, move  immediately  and  without  further  hesitation.  If  you  wait  until  the  tor- 
nado cloud  is  distant  one  mile,  you  have  at  least  sixty  seconds  in  which  to  run 
a  distance  of  thirty  rods,  supposing  that  you  are  obliged  to  cover  more  than  half  of 
the  destructive  path  of  the  storm.  In  an  average  case  you  will  probably  have  be- 
tween eighty  and  ninety  seconds  in  which  to  run  a  distance  of  twenty  rods.  In 
either  case  it  is  assumed  that  you  are  prepared  in  every  particular  to  wove  at  the 
very  instant  of  timely  warning.  Further,  it  is  assumed  that  you  have  been  watch- 
ing the  weather  of  the  day  and  understand  that  a  terrible  storm  is  imminent.  There 
is,  under  ordinary  circumstances,  no  reason  why  you  should  not  be  so  informed.  A 
tornado  cloud  does  not  come  out  of  a  clear  sky,  and  there  are  many  and  ample  signs 
of  its  approach. 

What  has  been  said  in  regard  to  the  directions  in  which  persons  should  move  when 
the  progressive  motion  is  prevailing  will,  for  all  practical  purposes,  apply  to  motions 
Nos.  1.  and  III.  With  respect  to  motion  No.  IV.  (the  zigzag),  the  following  prelimin- 
ary remarks  should  be  most  carefully  considered  :  While  possessed  of  this  motion 
the  tornado  cloud  crosses  from  one  side  of  the  central  line  of  movement  to  the 
other.  This  peculiar  motion  most  frequently  occurs  just  after  the  termination  of 
the  rising  and  /<////;/ %  motion  (No.  III. 'i.  so  that  when  you  see  the  tornado  cloud  de- 
scending to  the  earth  from  one  of  its  aerial  flights,  you  may  expect  the  zigzag  motion 
to  follow.  The  first  departure  of  the  tornado  cloud  from  the  general  path  of  the 
storm's  progress  is  to  the  left  or  on  the  north  side  of  the  path  ;  all  departures 
from  the  general  direction,  whether  left  or  right  movements  of  the  tornado  cloud, 
are  invariably  executed  to  the  eastward.  There  is  no  backward  movement  to  the  west: 
in  the  event  of  any  departure  it  ultimately  returns  to  the  central  line  of  movement. 
Having  these  points  well  in  mind,  you  are  prepared  to  act  when  the  exigency  oc- 
curs. When  the  departure  of  the  tornado  cloud  is  to  the  left  and  your  position  is 
at  any  point  near  the  central  path,  mure  directly  north  with  the  utmost  rapidity,  even 
if  the  cloud  is  at  a  long  distance  from  you.  Should  it  chance  that  your  distance 
from  the  cloud  is  reduced  to  twenty  or  forty  rods,  run  instantly  to  the  south,  bearing 
slowly  west.  This  movement  will  take  you  away  from  the  forward  and  return  action 
of  the  tornado  cloud.  Another  case  :  Suppose  your  position  to  be  the  same  as  just 
given,  viz  :  near  any  point  in  the  central  line  of  movement,  but  with  the  tornado  cloud 
just  crossing  over  the  line  to  the  south.  In  this  event  you  should  move  instantly 
and  directly  to  the  north,  bearing  slowly  west.  This  movement  will  also,  as  in  the 
case  previously  cited,  take  you  away  from  the  forward  and  return  action  of  the  tor- 
nado cloud. 

To  recapitulate  in  regard  to  tornado  cloud  motions  and  the  manner  of  movement 
with  respect  to  them  :  never  wait  until  the  tornado  cloud  is  almost  upon  you  before 
you  move,  and,  remember,  under  no  circumstances,  move  to  the  northeast,  east,  or 
southeast. 

Many  foolhardy  acts  have  been  committed  (perhaps  through  fear  and  excitement 
or  positive  ignorance)  by  persons,  which  have  resulted  in  death  or  terrible  injuries, 
because  they  tried  to  run  in  front  of  the  tornado  cloud,  thinking  they  could  outstrip 
it  in  such  a  race.  Others  have  attempted  to  cross  the  path  just  ahead  of  the  advanc- 
ing cloud,  feeling  that  they  could  reach  a  safe  distance  on  the  opposite  side  before 
the  funnel-shaped  monster  passed.  In  one  of  our  late  storms  a  person  assayed  this 
trip  with  two  horses  and  a  lumber  wagon,  confident  that  he  could  at  least  rush  his 
horses  across  the  apparently  narrow  path  of  storm  which  seemed  to  progress  within 
such  circumscribed  limits  ;  he  was  instantly  killed,  one  of  his  horses  dreadfully 
mangled,  the  other  seriously  injured,  and  the  wagon  a  total  wreck. 


TORNADO   CHARACTERISTICS.  15 

VJII. PROTECTION  OF  PROPERTY. 

What  can  be  done  to  lessen,  in  any  way,  the  actual  damage  (present  or  prospec- 
tive) to  property,  especially  buildings?  Since  it  is  utterly  impossible  to  move  them 
from  the  path  of  the  advancing  tornado  cloud,  and  quite  as  impossible  to  construct 
any  buildings  strong  enough  to  completely  resist  the  extraordinary  violence  of  the  tor- 
nado cloud,  it  is  equivalent  to  saying  that  you  can  never  expect  to  save  your  buildings, 
a  conclusion  to  which  all  thought  upon  the  subject  will,  sooner  or  later,  conform.  It  is 
advisable  that,  under  all  circumstances,  you  should  avoid  any  labor  especially  directed 
to  the  construction  of  any  buildings  whatsoever,  for  the'express  purpose  of  resist- 
ing the  violence  of  the  tornado  cloud.  Build  your  houses,  barns,  and  stores  as  you 
would  without  the  knowledge  of  a  tornado.  Other  things  being  equal,  a  frame  build- 
ing is  better  than  a  brick  or  stone  one.  The  former  will  hold  together  longer,  is  more 
elastic  (if  you  will  permit  the  term),  and  persons  seeking  refuge  within  its  walls  are 
much  less  liable  to  injury.  There  has  occasionally  been  evidence  to  show,  that 
of  all  frame  buildings,  those  constructed  with  a  hip  roof  and  a  story  and  a  half 
in  height,  were  the  best  able  to  resist  the  violence  of  the  tornado  ;  but  where  there 
are  cases  reported  of  this  class  of  buildings  being  saved,  there  are  as  many,  if  not 
more,  where  they  were  destroyed  precisely  as  any  other  frame  building  would  have 
been  under  similar  circumstances. 

It  matters  not  how  you  construct,  or  of  what  material,  if  your  building  rises  above 
the  surface  of  the  earth  (which  it  must  necessarily  do),  it  thereby  offers  obstruction 
to  the  advance  of  the  tornado  cloud,  and  it  will  go,  either  from  the  foundation,  or 
into  kindling-wood  and  a  distracted  mass  of  bricks  and  mortar,  in  spite  of  the  prop- 
agation of  any  theory  or  the  possibilities  of  architectural  skill.  The  narrow  belt 
of  destruction  renders  it  practicable  for  a  whole  state,  through  insurance  companies, 
to  bear  the  loss  that  occurs  at  any  one  point.  Cheap  buildings  and  general  insur- 
ance is  the  wisest  policy. 

IX BUILDING    SITES. 

"  In  regard  to  the  matter  of  buildings,  the  question  may  be  asked  whether  there  is 
not  some  choice  in  a  building  spot,  with  a  view  to  safety  from  the  violence  of  the 
tornado.  Many  persons  have  thought  that  if  their  house  or  barn  were  perched  upon 
some  high  "  divide  "  or  on  the  brow  of  a  steep  decline,  in  fact  upon  any  marked  rise 
above  the  surrounding  level,  the  tornado  cloud  would  rise  from  the  earth  and  pass 
over  it.  But  observation  seems  to  show  that  the  tornado  cloud  pursues  a  general 
course  to  the  northeast,  without  regard  to  the  character  of  the  earth's  surface,  and 
if  buildings  are  in  the  line  of  its  destructive  path,  whether  upon  a  hill,  in  a  valley, 
or  within  a  ravine,  they  are  liable  to  be  subject  to  its  violence.  Western  towns,  as 
a  rule,  are  not  built  upon  high  "  divides,"  but  more  frequently  sheltered  between 
neighboring  hills.  The  same  may  be  said  of  farm  buildings  ;  it  being  the  prevail- 
ing custom  to  select  building  spots  along  the  low  bottoms  of  streams,  for  conven- 
ience to  water  and  timber,  and  for  protection  from  the  continued  heavy  winds  that 
break  over  the  open  prairies.  Repeated  investigations  have  shown  that  buildings 
were  destroyed  with  as  great  violence  and  completeness  upon  high  lands  as  upon 
low  lands,  but  the  larger  number  in  valleys,  because  of  the  facts  above  cited.  In 
many  instances  the  funnel  cloud  has  passed  from  one  ridge  to  another,  doing  dam- 
age on  both,  but  skipping  the  intervening  depressions  ;  again  it  has  followed  high 
"divides"  for  several  miles  when  they  coincided  with  its  general  course  of  move- 
ment. Ridges  and  valleys  are  almost  invariably  crossed  at  right  angles  when  their 
courses  are  from  northwest  to  southeast. 


16  TORNADO   CHARACTERISTICS. 

X.  —  i»ru- 

Since  we  cannot  resist  the  power  of  the  tornado,  the  question  now  suggests  itself, 
what  precautionary  measures  can  be  taken  ?  That  which  remains  to  be  done  can  be 
accomplished  in  an  unostentatious,  and  quiet,  but  securd*  manner.  Every  man  can 
and  should  construct  a  "dug-out"r  at  some  suitable  point,  within  a  convenient  dis- 
tance of  his  house.  If  a  person  is  situated  within  a  town  or  city,  let  him  select 
some  portion  of  his  yard  for  the  purpose  ;  but  if  residing  in  the  country,  he  will  not 
be  confined  to  narrow  limits  in  the  selection  of  a  desirable  location.  Where  a  per- 
son living  in  a  village  has  no  yard,  he  must,  if  he  has  a  cellar,  construct  a  cellar- 
cave,  as  a  means  of  protection,  to  be  described  further  on.  With  respect  to 
the  '*  dug-out,"  in  no  event  should  the  roof  be  other  than  level  with  the 
surface  of  the  earth ;  in  fact,  it  is  highly  desirable  that  the  retreat  should 
be  so  constructed  that  the  ordinary  surface  of  the  earth  would  form  the 
roof  or  covering,  and  that  all  preparation  of  the  domicile  proceed  by  way  of 
excavation  and  supports  from  beneath.  As-  to  location,  there  is  not  much  to 
be  said ;  the  most  important  points  being :  convenient  distance,  a  high,  dry  place, 
and  possible  opportunities  to  excavate  into  the  northern  or  eastern  slope  of  a 
knoll  or  hill.  In  the  latter  instance,  the  entrance  way  would  suffer  less  from  the 
violence  of  the  storm,  providing,  perhaps,  that  "it  did  not  entirely  envelop  your 
retreat,  for,  in  that  event,  in  the  whirl  of  the  flying  debris,  all  sides  alike  would  be 
at  the  mercy  of  the  winds.  Having  decided  upon  the  location,  as  regards  your 
house  or  other  buildings,  prepare  to  sink  a  shaft,  say  four  to  six  feet  square,  the 
entire  depth  of  your  "dug -out"  From  either  the  northern  or  eastern  (better  the 
former)  wall  of  this  shaft,  cut  out  a  stairway  leading  upward  to  the  surface  of  the 
earth,  for  purposes  of  ingress  and  egress.  On  the  side  of  the  shaft  opposite  the 
stairway,  commence  the  excavation  for  the  enclosed  retreat.  The  size  of  the  room 
will,  of  course,  depend  upon  how  much  you  may  at  any  time  wish  to  secure  from 
injury.  Better  have  the  excavation  too  large  than  not  large  enough.  The  slight 
difference  in  the  expense  of  time  and  labor  may,  perhaps,  be  the  means  of  saving 
you  a  great  deal  when  you  least  expect  it.  The  entire  room  should  be  below  the 
surface  of  the  ground  a  distance  of  at  least  three  feet,  and  the  overhanging  roof  of 
earth  should  be  supported  from  beneath  by  heavy  timbers,  to  provide  against  any 
emergency,  like  the  dashing  of  heavy  debris  or  the  tramping  of  horses  and  cattle 
upon  it. 

In  the  event  of  a  tornado,  your  retreat  (**  dug-out  ")  may  be  entirely  buried  beneath 
huge  piles  of  debris,  therefore  everything  must  be  made  as"  secure  as  possible.  The 
entrance  door  should  be  made  of  the  heaviest  timbers  and  supported  between  cas- 
ings of  similar  strength  of  construction.  Arrangement  should  be  made  to  secure 
the  door  by  heavy  fastenings.  In  order  that  ventilation  may  be  provided  for,  two 
box  spouts,  squaring  eight  inches,  should  be  let  through  the  roof.  The  top  of  these 
spouts  must  be  level  with  the  surface  of  the  ground  and  protected  by  iron  gratings-.. 
Ventilation  may  also  be  provided  for  by  openings  through  the  upper  portion  of  the 
door,  and  these  also  should  be  protected  by  iron  gratings. 

The  "dug-out"  should  be  large  enough  to  contain  your  family  and  such  personal 
effects  as  are  considered  roost  valuable.  There  are  many  instances  where  persons 
have  lost  very  valuable  articles,  even  large  sums  of  money,  from  supposing  that  if 
such  things  were  placed  in  securely  bound  trunks  or  boxes  they  would  be  perfectly 
safe.  There  are  cases  where  iron-bound  trunks  and  even  iron  chests  (not  the  regular 
merchant's  safe)  especially  made  to  secure  valuable  articles,  have  been  crushed  or 
torn  to  pieces  and  the  contents  scattered  to  the  winds.  A  heavy  safe  might  resist 
the  force  of  the  wind  to  the  extent  that  it  would  not  be  broken  open,  bat  it  may  cost 
you  several  hundred  dollars,  and  even  then  yon  must  prepare  a  "  dug-out  "  for  your 
family.  Why  not  expend  this  money,  or  that  portion  of  it  which  is  found  necessary, 


TORNADO    CHARACTERISE  S.  17 

in  preparing  not  only  a  >ecure  refuge  for  your  family  but  also  sufficient  room  for  your 
valuables  ?  This  "dug-out "  need  not  prove  a  worthless  investment,  even  though  you 
do  not  experience  a  tornado.  On  the  principle  alone  that  "an  ounce  of  prevention 
is  worth  a  pound  of  cure, "the  outlay  cannot  be  considered  a  failure.  It  may  be  used 
tor  various  purposes  as  an  out-door  cellar.  If  it  proves  the  means  of  saving  a  life 
but  once  in  five  years  (your  own  among  the  number),  you  would  hardly  regret  the 
expenditure. 

There  is  still  another  kind  of  underground  protection  which  Can  be  prepared  to 
advantage,  if  you  are  provided  with  a  cellar,  either  under  your  house  or  store.  • 
Having  the  cellar,  cut  an  opening  (say  six  feet  high  and  four  feet  wide1!  into  the  west 
wall.  Carry  the  excavation  to  such  an  extent  underground  as  to  provide  sufficient 
p  room  for  your  family  and  valuable  personal  effects.  The  roof  of  this  cellar-cave 
should  be  composed  of  at  least  three  feet  (in  depth)  of  the  undisturbed  surface 
earth,  and  supported  from  beneath  by  heavy  timbers.  In  every  way  it  should  be 
made  as  secure  as  the  ••  dug-out."  The  provisions  for  ventilation  may  be  made 
through  the  root  or  entrance  door,  but  in  either  case  well  protected  by  iron  gratings. 

XI.  —  I'KorKClIoN     IN    CASES    *>K    KMKKGKNCY. 

In  case  you  are  possessed  of  a  building  that  has  no  dug-out  or  cellar-cave,  your  best 
plan  is  to  nioi-i  from  your  house,  or  from  the  location  where  you  are  at  the  instant 
stationed,  as  directed  in  the  previous  sections.  If  not  able  to  benefit  by  these 
directions,  retreat  instantly  to  your  cellar  and  place  yourself,  face  forward,  against 
the  r^v.'Ywall.  This  is  the  best  position  in  any  cellar.  If,  for  any  reason,  you  cannot 
get  to  the  li'cst  TI'<J//,  take  your  position  (the  next  best  i,  face  forward,  against  the  south 
wall,  but  as  near  the  southwest  corner  as  possible.  In  case  the  building  is  removed  from 
the  foundation,  it  will  always  be  carried  above  and  over  you,  or,  if  torn  to  pieces,  the 
debris  will  be  instantly  removed  to  the  eastward,  t  'ndcr  no  circumstances*  whether  in  a 
building  or  a  cellar,  fats  a  position  in  ,1  northeast  room,  in  u  northeast  corner,  in  an  cast 
room,  or  against  an  cast  wall.  Remember  that  the  tornado  cloud  invariably  moves  in 
a  northeasterly  direction.  Persons  have  been  instantly  killed,  or  terribly  crippled,  for 
no  other  reason  than  that  they  ignorantly  threw  themselves  in  the  very  grasp  of  the 
monster  cloud. 

The  rule  regarding  the  movement  to  the  northeast  must  be  obeyed.  The  northeast 
quarter  is  a  fatal  position,  whatever  may  be  said  ^about  destruction  to  life  or  prop- 
erty  in  anv  other.  If,  unfortunately,  you  are  close  pressed  by  the  advancing 
cloud,  never  remain  standing  and  attempt  to  weather  the  storm,  but  throw  your- 
self prone  ^f'ace  downward)  upon  the  ground,  head  to  the  east,  and  arms  over  the 
head,  to  protect  it.  If  you  should  chance  to  be  near  a  large  stone  or  stump,  or  some 
lu.uv.  low  object  firmly  imbedded  in  the  ground,  take  a  position  directly  to  the  east 
of  it.  lying  prone  upon  the  ground,  head  toward  the  object,  protecting  the  former 
with  your  folded  arms.  This  advice  is  given  in  the  event  of  extreme  necessity., 
where  other  and  better  oppoit unities  are  unavailable  or  have  been  forfeited.  It  is 
better,  if  possible,  never  to  trust  yourself  behind  or  about  any  movable  object 
located  within  the  centre  of  the  storm's  path  ;  by  all  means  not  a  tree  or  anything 
that  rises  some  distance  above  the  surface  of  the  ground.  If  you  can  get  out,  never 
remain  in  a  house,  or  any  other  building  that  is  at  all  likely  to  be  torn  down  or 
lemoved  from  its  foundation.  If  forced  to  remain  in  a  building  without  a  cellar. 
alwa\>  take  a  position  against  the  :«v.»7  or  south  wall  (better  the  former),  either  prone 
(face  downward)  upon  the  rloor  or  standing  with  your  back  to  the  wall. 

In  any  building,  always  take  your  final  position  on  the  first  or  ground  rloor  or  in 
the  cellar.  Never  stand  or  lie  in  front  of  a  doqr  or  window,  or  near  a  stove  or 
IHMVV  piece  of  furniture.  Make  every  effort  to  get  into  the  west  room  and,  if  possi- 
ble, before  the  onslaught,  remove  all  furnituie  from  the  western  portion.  If  you 

2 


18  TORNADO    CHARACTERISTICS. 

have  the  necessary  time,  shut  tightly  every  window  and  door  in  the  building  within 
which  you  may  be  located  at  the  time  of  the  storm. 

Never  take  refuge  in  a  forest,  in  a  small  grove  of  trees,  in  an  orchard,  in  a  build- 
ing, or  near  a  fence  of  any  kind,  unless  such  obstruction  is  entirely  out  of  the  line  of 
the  storm. 

If  possible,  always  open  the  doors  of  your  out-buildings  and  let  your  stock  loose, 
driving  them  to  the  north,  as  before  directed;  or,  if  the  tornado  cloud  seems  about 
to  pass  to  the  north  of  your  buildings,  your  stock  should  be  driven  southward,  the 
rules  being,  of  course,  the  same  as  for  human  beings. 

XII.  — I'KOTKCTION     IN    TOWNS    AND    CITIES. 

With  regard  to  the  protection  of  life  and  property  in  towns  and  cities  liable  to  be 
visited  by  tornadoes,  what  has  already  been  suggested  in  the  matter  of  north  and 
south  movements,  "  dug-outs,"  and  cellar-caves,  will,  of  course,  apply  here.  But  where 
a  large  number  of  persons  are  congregated,  each  intent  upon  his  particular  business, 
some  provision  should  be  made  for  the  mass  of  inhabitants  who  are  performing  their 
various  duties  in  and  out  of  doors,  and  who,  by  reason  of  their  peculiar  situation  or 
labor,  cannot,  if  they  would,  stop  to  study  the  prognostics  of  the  sky. 

With  regard  to  this  matter  a  tew  suggestions  will  be  offered  which  may  not  be  amiss. 
On  any  day  when  the  weather  conditions  presage  the  probable  approach  of  a  vio- 
lent wind  storm,  it  should  be  the  duty  of  those  in  authority  to  deputize  certain 
persons,  one  or  more  in  each  ward,  the  number  depending  upon  the  sixe  of  the  town, 
to  watch  the  character  of  the  sky  and  approach  of  the  storm,  and.  if  a  tornado,  to 
give  timely  warning  of  its  advance  to  the  various  families  in  their  respective  wards, 
and  take  charge  of  the  removal  of  persons  and  property  to  places  of  safety.  In  the 
matter. of  warning  the  various  portions  of  the  town,  it  would  probably  be  to  advantage 
to  make  use  of  the  church  and  school  bells,  by  ringing  them,  in  some  peculiar  man- 
ner, to  be  decided  upon  by  previous  arrangement  and  generally  understood.  It 
should  be  well  known  that  the  persons  above  referred  to  are  possessed  of  special 
authority  while  performing  their  duties.  They  should  be  cool,  brave,  active,  intel- 
ligent, and  judicious  men.  They  should  completely  understand  the  situation,  know 
precisely  what  is  needed  and  how  to  supply  it.  All  men  should  appreciate  the  situ- 
ation of  these  persons,  and  avoid  confusion,  by  a  strict  compliance  with  orders.  It 
will  not  be  necessary  for  these  persons  so  deputized  to  be  adepts  in  the  science  of' 
meteorology,  or  to  devote  their  time,  from  the  ist  of  April  until  the  ist  of  September, 
exclusively  to  observations  of  the  sky. 

The  signs  (as  before  described)  of  tornado  cloud  formation  and  approach  are  dis- 
tinct and  sufficiently  suggestive  to  afford  opportunity  for  timely  and  concerted  action. 
The  time  for  action  will  necessarily  be  limited,  and  the  watch  need  not  commence 
until  there  is  every  reason  to  believe  that  such  a  course  is  absolutely  necessary.  ]\o 
one  should  smile  at  the  novelty  and  minuteness  of  this  arrangement,  or  at  the  idea 
of  employing  weather  guards  at  western  towns.  It  is  a  means  of  precaution  very 
competent  for  the  protection  of  life  and  property. 

XIII. STATK    WKATHKR    SERVICKS. 

The  State  Weather  services  of  Ohio,  Indiana,  Kansas,  Nebraska,  Missouri,  Iowa, 
and  other  states,  under  the  efficient  supervision  of  their  several  directors,  are  doing 
most  excellent  general  meteorological  work.  They  should  receive  the  hearty  aid 
and  appreciation  of  the.  people  and  of  the  legislatures  of  their  respective  states. 
Every  state  should  have  a  weather  service,  every  township  an  observer,  and  every 
chief  observer  at  the  county  seat  be  authorized  to  receive  monthly  reports  from  the 
various  observers  within  his  jurisdiction  and  forward  the  same,  monthly,  to  the  state 


TORNADO    CHARA-CTKI 

director  of  such  service.  Each  director  should  have  the  time  and  force  at  his  dis- 
posal to  thoroughly  digest  the  meteorological  conditions  of  each  and  every  month, 
throughout  the  year,  preparing  and  publishing,  at  the  termination  of  each  month, 
and  also  at  the  close  of  each  year,  a  general  summary  of  atmospheric  phenomena 
coupled  with  the  evidence  of  earnest  and  well  directed  efforts  toward  comparative 
study  and  practical  results. 

Such  funds  as  are  necessary  to  carry  forward  a  work  of  this  kind  should  yearly  be 
appropriated  by  the  state  legislature.  As  so  organized,  and  when  in  working  order, 
each  state  weather  service  should  co-operate  with  the  United  States  Weather  Service, 
at  Washington,  and  thus  complete  a  system  of  meteorological  work  which  would 
effect  a  marvelous  advance  in  the  study  of  this  most  important  science.  » 

There  is  no  country  on  the  face  of  the  globe  where  meteorology  can  be  studied 
with  so  much  advantage,  practically  and  scientifically,  as  in  North  America.  The 
elementary  principles  of  meteorology,  especially  in  regard  to  storms,  should  be 
taught  in  every  high  school.  In  the  colleges  and 'universities  an  advanced  course 
should  be  prescribed.  Wild  speculations  regarding  the  laws  of  the  weather  are 
exceedingly  rife,  touching  every  branch  of  the  science,  and,  in  view  of  this,  facts  and 
principles  should  alone  be  considered  in  conducting  the  prescribed  course  of  any 
educational  institution. 

It  is  not  believed  that  in  this  concise  presentation  of  important  facts  the  results 
altogether  meet  the  supreme  desire,  or,  perhaps,  the  hope,  of  the  people  interested 
in  the  subject  of  tornadoes.  Such  desires  or  hopes  may  never  be  realized,  not,  at 
least,  until  the  investigation  and  analysis  of  these  phenomena  have  been  perfected  ; 
yet  you  have  before  you  in  very  brief  form  the  results  of  over  five  years  of  labor  and 
an  examination  of  over  600  tornadoes. 

XIV. THE    OBSERVATION    AND    RECORD    OF    TORNADOES. 

In  order  to  be  prepared  for  the  possible  appearance  of  a  tornado,  so  far,  at  least, 
as  local  indications  are  concerned,  let  every  person  situated  in  those  regions  of 
country  where  the  tornado  is  of  yearly  occurrence  commence  to  carefully  observe 
and  record  the  daily  changes  in  the  face  of  the  sky,  the  variations  of  temperature, 
the  direction  of  the  wind,  and  the  character  and  development  of  clouds.  Not  that 
any  person  should  devote  most  or  all  of  his  time  to  this  work  of  observation,  nor 
even  all  of  his  spare  time,  but,  for  the  sake  of  regularity  and  uniformity,  certain 
hours  for  regular  work  of  this  nature  are  advised,  viz:  3,  7,  and  n  a.  m.,  3,  7,  and  n 
p.  in.,  Washington  time. 

Should  unusually  interesting  phenomena  occur  during  the  period  between  these 
hours  of  observation,  it  would  be  advisable  to  increase  the  number  of  observations, 
making  these  at  as  short  intervals  as  the  importance  of  the  case  demands.  By 
means  of  these  frequent  observations,  every  feature  of  the  storm  becomes  the 
subject  of  inquiry  and  quite  probably  more  important  results  attained.  For  purposes 
of  investigation  of  tornadoes  the  observations  need  not  continue  throughout  the 
entire  year,  at  least  in  the  northern  and  western  states,  although  such  a  length  of 
record  would  be  of  great  value  for  other  purposes  ;  but  observations  should  certainly 
begin  by  the  ist  of  April  and  continue,  unremittingly,  until  at  least  the  ist  of  Sep- 
tember. Observations  through  the  autumn  can  be  maintained  with  profit. 


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